QUESTIONS:
How do I open Microsoft Office 2007 documents in Microsoft Office 2003?
How do I install the Office 2003 Compatibility Pack?
ANSWER:
To open, edit, and save documents, workbooks, and presentations in the file formats new to Microsoft Office Word, Excel, and PowerPoint 2007 in Office 2003, you must have the Office Compatibility Pack installed.
Note: There currently is no compatibility pack available for Mac OS X Office 2004 and Office X.